A sign reading 'Why' is placed on on a wall near the Olympia shopping mall, where the shooting rampage started, in Munich, GermanyMichael Dalder/ Reuters

The gunman who killed nine people in Munich before killing himself had stated his hatred for Turkish people beforehand as well as expressing his pride at sharing the same birthday as Adolf Hitler, it has emerged.

Until now, investigators had described David Ali Sonboly as a psychologically disturbed 18-year-old who had endured bullying and had not been active in right-wing circles in the city.

But the the Local.de ran a piece which originated in the Frankfurter Allgemeine Zeitung about how Sonboly had said he was proud be German and Iranian, which he considered made him an Aryan.

The paper said he also had a feeling of superiority towards Turks and Arabs, as investigators look into whether he deliberately targeted foreigners in the rampage on on 22 July.

Of his nine victims, seven were Muslims. He also made much of his 20 April birthday, the same as Hitler.